Master AQA A Level Chemistry (7405) with this examiner-backed study package. Grounded in insights from the 2022-2024 papers, this guide covers exact timing strategies, strict mark-scheme expectations for mechanisms and calculation units, key inorganic observations, and high-yield calculator techniques to secure your target grade.
読了時間 4 分更新日: 2026年6月21日
試験の概要
試験数
3
満点
300
制限時間
6時間
出題形式
4
試験
時間
配点
問題数
配点比率
出題形式
Inorganic and Physical Chemistry
2時間
105
9
35%
Structured Explanation, Theory, and Calculations
Organic and Physical Chemistry
2時間
105
11
35%
Structured Explanation, Mechanism Drawing, and Calculations
Synoptic
2時間
90
35
30%
Structured Practical and Synoptic Questions, Multiple Choice
評価段階
A*ABCDEU
電卓の規定
A scientific or graphical calculator that meets JCQ regulations may be used (some GCSE Mathematics and Science papers are non-calculator). Graphical calculators must be set to exam mode; you must clear any stored programs, notes or data before the exam, and the calculator must not be able to retrieve stored text or formulae.
AO1: AO1: Knowledge and understanding of scientific ideas, processes, techniques and procedures. (35%)
AO2: AO2: Apply knowledge and understanding of scientific ideas, processes, techniques and procedures. (40%)
AO3: AO3: Analyse, interpret and evaluate scientific information, ideas and evidence. (25%)
過去問と採点基準にもとづいて作成（2022–2024）。
電卓プログラム
Graph: zeros, intersections & turning points
Graphical calculator / GDC (exam mode)
目的: Plot a function to read its roots (zeros), points of intersection, and maxima/minima.
使う場面: Checking solutions, sketching, or solving where an analytic method is hard.
手順
Graph the function(s) and use the built-in zero, intersect and maximum/minimum tools.
試験での注意: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
Numerical equation solver
Graphical calculator / GDC (exam mode)
目的: Solve an equation or find a variable numerically when an algebraic route is long or implicit.
使う場面: Iterative or implicit equations, or to confirm an algebraic solution.
手順
Use the equation/zero solver, entering the equation and a sensible starting estimate.
試験での注意: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
Numerical integration & differentiation
Graphical calculator / GDC (exam mode)
目的: Evaluate a definite integral \(\int_a^b f(x)\,dx\) or a gradient \(f'(x)\) at a point.
使う場面: Checking calculus answers, or where only a numerical value is needed.
手順
Use the GDC's numeric integral / derivative function with the limits or the point.
試験での注意: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
Statistics & probability distributions
Graphical calculator / GDC (exam mode)
目的: 1-var/2-var statistics, linear regression, and cumulative binomial / normal / Poisson probabilities without tables.
使う場面: Statistics questions and hypothesis tests.
手順
Enter data in the statistics editor, or use the distribution menu (binomial cdf, normal cdf, …).
試験での注意: Allowed under JCQ rules, but you must still show your method — an unsupported calculator answer earns no method marks. Clear all stored programs, notes and data (graphical calculators in exam mode) before the exam.
よくあるミス
1high影響する配点: 2Chemical equilibria, Le Chatelier’s principle and Kc
Failing to convert volume from cm³ to dm³ in Kc and Ka calculations, or forgetting to square terms in the rearrangement of rate equations.
回避方法: Always check units before substituting values. Divide volume in cm³ by 1000 to convert to dm³ before calculating concentrations. Write down the rearranged rate equation and verify powers match orders of reactants.
2high影響する配点: 4Introduction to organic chemistry
Drawing curly arrows that do not originate clearly from a lone pair or a covalent bond, resulting in zero marks for organic mechanisms.
回避方法: Draw mechanisms slowly and carefully. Start your arrow directly on the lone pair or the center of the bond, and point it directly to the target atom to show bond formation/cleavage.
3medium影響する配点: 3Atomic structure
In Time Of Flight (TOF) calculations, failing to convert the isotopic mass from g/mol to kg/ion by dividing by both Avogadro's constant and 1000.
回避方法: Use the conversion formula: mass of 1 ion in kg = (molar mass in g / Avogadro's constant) / 1000.
4high影響する配点: 1Equilibrium constant Kp for homogeneous systems
Using square brackets instead of round brackets in Kp expressions, which is strictly penalized by AQA examiners.
回避方法: Write Kp expressions strictly using round brackets and partial pressure notation, e.g., Kp = (p(C))^c / ((p(A))^a * (p(B))^b). Square brackets are exclusively reserved for concentration (Kc).
5medium影響する配点: 1Optical isomerism
Describing the overall molecule as planar rather than specifically citing the planar carbonyl group when justifying racemic mixtures.
回避方法: Always state that the 'planar carbonyl group' or 'planar C=O carbon' is attacked with equal probability from above or below. Avoid stating that the entire molecule is planar unless that is chemically correct and relevant.
6medium影響する配点: 2Transition metals
Writing incorrect chemical equations for the reactions of transition metal 3+ ions with sodium carbonate, specifically omitting carbon dioxide gas.
回避方法: Remember that aqua 3+ ions are highly acidic due to high charge density. When reacted with carbonate ions, they undergo an acid-base reaction forming carbon dioxide gas and a neutral hydroxide precipitate. Always write the gas and water in the equation.
7medium影響する配点: 1Amount of substance
Assuming the error in a burette reading is only for a single reading, rather than multiplying by 2 for the total titration error.
回避方法: Since a titre is calculated by subtracting an initial volume from a final volume, two readings are taken. Multiply the uncertainty of a single reading by 2 to calculate the total titration uncertainty.